Turn back pulleys or rollers of powered continuous loop belt conveyors are known to be specially adapted to include embedded or internally housed permanent magnets. Where such turn back rollers or pulleys are so adapted, they advantageously cause the continuous loop conveyor to additionally perform an automatic ferrous metal attracting and loading function. Where, for example, such a magnetically adapted conveyor pulley is positioned over a moving stream of materials (or a relatively moving stream of materials resulting from movement of the conveyor assembly) ferrous metal parts and/or scrap steel contained within the stream are advantageously drawn out of such stream and into a magnetically attached and contacting relationship with the conveyor belt at points radially overlying the magnetic pulley. The continuously looping motion of the conveyor belt over the magnetic pulley draws the ferrous metal parts or scrap steel along the conveyor and away from the magnetic pulley for conveyance along the conveyor belt to a desired remote location for disposal or separate storage.
A common drawback or deficiency of such magnetic conveyor pulley and conveyor belt combinations is an insufficiency or deficit in the magnetic strength and density of lines of magnetic flux which extend from the pulley at the conveyor's end. As a result of such deficiency, such common magnetic pulley and conveyor combinations have only a limited capability to attract and convey away ferrous magnetic parts and scrap materials.
Such magnetic attraction deficit commonly results from an adoption of an intuitive mechanical arrangement of the polar axes of the permanent magnets which are contained within or supported by the magnetic conveyor pulley. Just as the lateral cross-sectional shape of a conveyor pulley is circular, commonly known magnetic adaptations of conveyor pulleys have arranged the polar axes of the contained or supported permanent magnets to emanate magnetic flux outwardly in a substantially circular radial array. Such radial arrays of magnetic flux are known to result from either one of two commonly known modes of mounting of permanent magnets within or upon a continuous loop conveyor's pulley. In one such mode, the permanent magnets are arranged in multiple N,N,S,S,N,N . . . polar orientation chains, each such magnet chain extending parallel with the pulley's rotation axis and such magnet chains being arranged circumferentially about the pulley's annular outer periphery. In the other mode, U-shaped or horseshoe magnets which present their north and south poles at paired distal ends of the magnet's arms are similarly arranged in a radial array about the pulley. Where such U-shaped magnet configuration is utilized, a paramagnetic axle core within the pulley is often utilized as a magnetic armature for completing the “U” configuration of such north and south magnet arm pairs. Both modes of conveyor pulley magnet adaptation described above produce a circumferential array and extension of lines of magnetic flux, and in both the resultant magnetic flux is undesirably weak in all radial directions.
The instant inventive assembly for loading and conveying ferrous metal articles solves or ameliorates problems and deficiencies discussed above by configuring the magnetically adapted conveyor pulley to be or function as a substantially single magnet having a north/south polar axis which intersects the pulley's axis of rotation at a perpendicular or substantially 90° angle, and which crosses the entire lateral cross-sectional diameter of the pulley.